The present invention relates, in general, to directional control of optical emissions, and more particularly, to a system for dynamically steering a light beam toward a remote reception point.
Speed and power requirements, as well as technological advances, have increased the use of optics in electronic systems. The adaptation of optical interconnection to computer systems has precipitated an increasing requirement to be able to control the path of a light beam. Such applications as reconfigurable optical interconnection, optical switching, or self-aligning laser systems, such as a compact disc player, would benefit from such an ability.
Previously, means of directing a light beam toward a remote reception point, such as a sensor, a receiver, a waveguide, or an optical fiber, consisted primarily of reflecting the beam using a multi-position mirror, or diffracting the beam using a multi-position holographic element. In one such approach, a mirror was driven by a motor which changed the orientation of the mirror. A light beam aimed at the surface of the mirror was thus reflected in a direction determined by the angle of incidence upon the mirror. Another approach utilized a linear motor to change the position of a holographic scanner relative to the light beam. The angle at which the light beam was diffracted by the holographic scanner was thus changed.
Still another approach toward steering a light beam again relied upon reflection from a mirrored surface. In this case, an optical switch was built by having the mirrored surface assume one of two positions. The first position directed the beam of light toward a fiber optic receptor. The second position directed the beam of light away from the receptor. The mirrored surface was supported upon a silicon pedestal about which it could pivot. Under each end of the mirrored surface was located an electrode. A potential applied between the mirrored surface and one electrode caused the mirrored surface to pivot toward the electrode. A potential applied between the mirrored surface and the other electrode caused the mirrored surface to pivot back toward the other electrode. This established the two positions for the optical switch.
The prior art was subject to a number of limitations. Solutions involving motors could not be integrated upon a silicon chip. Mechanical couplings reduced the reliability of the electronic systems. The optical switch was limited to two positions, and also involved deforming silicon, which opened up the possibility of structural failure during operation.